320 
in which: 
Zz AV)\SA VY, PAN Leid Mi Ves (8) 
SADE EH re err 
Herein 4,...4,41 have the values which follow from (6) conse- 
quently 2(2V) is the change in volume and 2 (4H) the change in 
entropy, which occur at the phases-reaction (5). 
The equilibrium, being monovariant, is represented in the P, 7- 
diagram by a curve that we shall call /, its direction is defined 
by (7). 
When we follow this curve #, «, y,...a,y,... and consequently 
also 4, 4,... change from point to point aiong this curve. When in 
a definite point g of this curve 2, becomes equal to zero, then in 
(8) 4g Vz becomes = 0 and 4, H,=0. Then in the point q is true: 
(ey see bs 
al) mea: vere a aa 
Now the equilibrium /# passes in point q under consideration 
into an equilibrium: 
Epa. Bgg Bnei: re ACE 
viz. into one of the equilibria Zr of n components in » phases 
between which a phases-reaction: 
Wier Ap ay Edges Wi cen OH et = Og 
may occur. We have considered those equilibria Hr before. This 
equilibrium (11) is also monovariant and is represented in the P, 7- 
diagram by a curve, the turning-line HR of the region: 
(FS FS Ha Fa ee eed 
Formula (9) is also valid for this turning-line. It is apparent from 
our considerations : 
“the curve which represents the equilibrium : 
ashe Fig eta nde 
‘ig situated in the P,7-diagram in the common part of the x + 1 
“regions (F‚)(F)... (Bn); when in a point q of this curve the 
“phase /, does not participate in the reaction, the curve touches 
“the turning-line of the region (/;,) in this point g. In general n-+-1 
“of those tangents may occur’. 
When we apply this to the binary equilibrium H= F+ L + G, 
in which F, L and G represent a binary compound, liquid and 
vapour, it then follows that the curve / must be situated within 
the three regions #+ L, F+ G and L+ G. When in a point a 
the liquid Z obtains the same composition as #, the curve / touches 
the limit-curve Er= F'+-L (consequently the melting-line of /’) 
